1. Field of the Invention
The present invention generally concerns the sequencing of bases in nucleic acid molecules by repeated separate polymerasecathylzed covalent phosphodiester covalent linkage of each of four deoxyribonucleotide triphosphate to template DNA. The present invention particularly concerns an improved method and apparatus for nucleic acid base sequencing by annealing a primer to a nucleic acid template, extension of the primer and direct step-wise detection of added bases, without the use of nucleic acid fragments, extrinsic labeling or electrophoresis.
2. Description of the Prior Art